const inputs = document.querySelectorAll(".input")

function addcl(){
    let parent = this.parentNode.parentNode;
    parent.classList.add("focus")
}

function remcl(){
    let parent = this.parentNode.parentNode;
    if(this.value === ""){
        parent.classList.remove("focus")
    }
}

inputs.forEach(input => {
    input.addEventListener("focus",addcl);
    input.addEventListener("blur",remcl);
})